CVE-2025-8535 is a cross-site scripting (XSS) vulnerability identified in the cronoh NanoVault product, specifically affecting versions 1.2.0 and 1.2.1. The vulnerability resides in the executeJavaScript function within the /main.js file of the xrb URL Handler component. This flaw allows an attacker to inject malicious JavaScript code that can be executed in the context of the victim's browser when interacting with the vulnerable NanoVault application. The vulnerability is remotely exploitable without requiring authentication, although it does require some user interaction (e.g., clicking a crafted link or visiting a malicious page). The CVSS 4.0 base score is 5.1, indicating a medium severity level. The attack vector is network-based with low attack complexity and no privileges required, but user interaction is necessary. The vulnerability impacts the confidentiality and integrity of the user's session and data by potentially allowing session hijacking, credential theft, or unauthorized actions performed on behalf of the user. The vendor was notified early but did not respond, and no patches or mitigations have been publicly released. Although no known exploits are currently observed in the wild, the public disclosure of the vulnerability increases the risk of exploitation by attackers. Given that NanoVault is a wallet application, likely related to cryptocurrency or digital asset management, the impact of successful exploitation could lead to theft or loss of digital assets or sensitive user information.

For European organizations using cronoh NanoVault, especially those involved in cryptocurrency management, financial services, or digital asset custody, this vulnerability poses a tangible risk. Exploitation could lead to unauthorized access to wallet contents, theft of digital assets, or compromise of user credentials. This can result in financial losses, reputational damage, and regulatory scrutiny under GDPR and other data protection laws. Since the vulnerability requires user interaction, phishing campaigns targeting European users could be a likely attack vector. Organizations relying on NanoVault for secure asset management may face operational disruptions and loss of trust from clients. The lack of vendor response and absence of patches increases the urgency for organizations to implement compensating controls. Additionally, the medium severity score suggests that while the vulnerability is not critical, it is sufficiently serious to warrant immediate attention, especially in sectors where asset security is paramount.

Given the absence of official patches, European organizations should implement the following specific mitigations: 1) Restrict and monitor the use of NanoVault versions 1.2.0 and 1.2.1, and consider temporarily suspending their use until a patch is available. 2) Employ web application firewalls (WAFs) with custom rules to detect and block suspicious payloads targeting the executeJavaScript function or the xrb URL Handler component. 3) Educate users about phishing risks and the dangers of clicking on untrusted links, emphasizing the potential for XSS exploitation. 4) Implement Content Security Policy (CSP) headers to limit the execution of unauthorized scripts within the NanoVault web interface. 5) Monitor network traffic and application logs for unusual activity indicative of exploitation attempts. 6) If feasible, conduct code reviews or sandbox testing of the NanoVault application to identify and block malicious inputs. 7) Engage with the vendor or community to encourage prompt patch development and share threat intelligence. 8) Consider alternative wallet solutions with active security support if mitigation is not feasible.